The present invention relates to a technical field of the airbag apparatus in which the airbag stored near the boundary between the ceiling of the vehicle body and the side portion of the vehicle body along the fore-and-aft direction of the vehicle body is inflated and deployed like a curtain downwardly of the vehicle body by gas from an inflator in case of emergency such as a side crash of the vehicle where a load in excess of a prescribed value is applied to the side surface of the vehicle body, and more specifically, to the technical field of the airbag apparatus being provided with a gas inlet passage for introducing gas from the inflator into the airbag.
The airbag apparatus of this type is constructed in such a manner that the airbag is inflated and deployed along the window or the like on the side door by gas from the inflator in case of emergency such as a side crash of the vehicle where a load in excess of a prescribed value is applied to the side surface of the vehicle to prevent the passenger from being crashed to the side portion of the vehicle body and protect him/her.
Incidentally, in the airbag apparatus in this arrangement, the airbag is arranged at the upper portion of the vehicle body extending longitudinally in the fore-and-aft direction of the vehicle along the window or the like on the side door near the boundary between the ceiling of the vehicle and the side portion of the vehicle body in a folded state, and constructed so as to be inflated downwardly of the vehicle body by gas introduced into the airbag via the front or rear end of the airbag. However, since the airbag is elongated in the fore-and-aft direction of the vehicle, the timing of introduction of gas introduced from the front or the rear end of the airbag differs depending on the positions in the fore-and-aft direction of the airbag, and thus it is difficult to inflate and deploy the airbag uniformly across the fore-and-aft direction.
Accordingly, the airbag apparatus in which a gas inlet passage is disposed in the fore-and-aft direction in the airbag having the prescribed number of gas exhaust ports at prescribed intervals, so that the airbag is inflated and deployed by introducing gas from the inflator in the fore-and-aft direction of the airbag through the gas inlet passage, and blowing off gas from the respective gas exhaust ports into the airbag is disclosed for example in Japanese Patent Application Publication No. 11-314555 and Japanese Patent Application Publication No. 11-301394. According to the airbag apparatus disclosed in these patent publications, gas from the inflator is introduced in the fore-and-aft direction of the airbag, and thus the airbag is inflated and deployed more uniformly across the fore-and-aft direction.
However, in the airbag apparatus disclosed in the respective patent publications described above, the airbag is merely inflated and deployed, but not inflated and deployed so as to protect the passenger more effectively.
In the conventional automotive vehicles or the like, a resilient member such as a garnish is provided in the side portion of the vehicle body, so that it can protect the passenger when the passenger abuts against the side portion of the vehicle body by a load applied to the side portion of the vehicle body, which is not heavy enough to inflate and deploy the airbag. However, when the airbag apparatus is provided in the side portion of the vehicle body, the gas inlet passage is located at the upper portion of the vehicle body near the boundary describe above, whereby it is difficult to protect the passenger effectively when he/she abuts against the side portion of the vehicle body.
With such a circumstance in view, an object of the present invention is to control inflation and deployment of the airbag and to provide an airbag apparatus that enable the airbag to be inflated and deployed so that the passenger is protected more effectively.
Another object of the present invention is to provide an airbag apparatus that enables the airbag to protect the passenger more effectively when the passenger abuts against the side portion of the vehicle body by a load that is not heavy enough to inflate and deploy the airbag.
In order to solve the problem described above, the invention is an airbag apparatus at least comprising: an airbag stored in the upper portion of the side portion of the vehicle body along the fore-and-aft direction of the vehicle body; and a gas inlet passage disposed in the airbag in the fore-and-aft direction for introducing gas from the inflator into the airbag in the fore-and-aft direction and then blowing it into the airbag from the gas exhaust port, so that the airbag is inflated and deployed toward the lower portion of the vehicle body by blowing gas introduced through the gas inlet passage into the airbag through the gas exhaust port in case of emergency such as a side crash of the vehicle, characterized in that an airbag inflation and deployment control means for controlling inflation and deployment of the airbag is provided.
The airbag inflation and deployment control means controls the direction of inflation and deployment of the airbag in such a manner that the airbag inflates and deploys along the inner surface of the side portion of the vehicle body.
The airbag inflation and deployment control means is mounted so that the gas exhaust port opens along the inner surface of the side portion of the vehicle body.
The invention, in one embodiment, is characterized in that the airbag inflation and deployment control means controls inflation and deployment of the airbag by controlling the direction of gas blown from the gas exhaust port so that the direction of gas blown at the beginning of inflation and deployment of the airbag differs from the direction of gas blown during subsequent inflation and deployment of the airbag.
The invention is characterized in that the airbag inflation and deployment control means is formed of a projection projecting inwardly of the gas inlet passage in conjunction with the gas exhaust port.
The invention is characterized in that the gas inlet passage is formed of material such as aluminum or the like that is not deformed by a load applied by the passenger when he/she abuts therewith under the normal condition, but is deformed when the passenger abuts therewith with a relatively heavy load, which is not less than a prescribed value but not heavy enough to inflate and deploy the airbag, is applied to the side surface of the vehicle.
[Operation]
In the airbag apparatus of the present invention in this structure, inflation and deployment of the airbag are controlled in various manners by the airbag inflation and deployment control means, and thus the airbag is inflated and deployed so that the passenger is protected more effectively.
Especially, in one embodiment, the direction of inflation and deployment of the air bag is controlled to the direction along the inner surface of the side portion of the vehicle body by the airbag inflation and deployment control means. In this arrangement, the airbag can be inflated and deployed quickly, smoothly and reliably in the relatively narrow space between the inner surface of the side portion of the vehicle body and the passenger along this inner surface. Therefore, the airbag that is inflated and deployed in such a manner, the body of the passenger such as the head or the like is reliably prevented from being crashed against the side portion of the vehicle body in case of emergency, and thus the passenger is protected more effectively.
In one embodiment, the direction of deployment of the airbag can be controlled only by orienting the gas exhaust port of the gas inlet passage in the direction along the inner surface of the side portion of the vehicle body, the construction of the airbag inflation and deployment control means can be significantly simplified.
In one embodiment, the direction of gas blown from the gas exhaust port is controlled to be different between the timing at the beginning of inflation and deployment and during subsequent inflation and deployment of the airbag by the airbag inflation and deployment control means. In this arrangement, the direction of gas blown at the beginning of inflation and deployment of the airbag can be suitably controlled, and thus the airbag starts inflation and deployment so as to slide into the narrow space between the passenger and the inner surface of the side portion of the vehicle body at the beginning. Then the airbag is inflated and deployed by relatively large amount of gas blown during subsequent inflation and deployment of the airbag further quickly and sizably. In this way, since inflation and deployment of the airbag are controlled in two stages of initial inflation and deployment, and subsequent main inflation and deployment, the airbag can be inflated and deployed more quickly and reliably. Therefore, the body of the passenger such as the head or the like can be prevented more reliably from being crashed against the side portion of the vehicle body in case of emergency by the airbag inflated and deployed in such a manner and thus the passenger can be protected more effectively.
In a variant wherein inflation and deployment of the airbag can be controlled only by providing a projection projecting into the gas inlet passage in conjunction with the gas exhaust port, the construction of the airbag inflation and deployment control means can be significantly simplified.
When the body of the passenger such as the head abuts against the gas inlet passage relatively strongly by applying a load, which is not heavy enough to inflate and deploy the airbag, to the side surface of the vehicle body, the gas inlet passage deforms. Deformation of the gas inlet passage can absorb and alleviate the impact energy of the passenger against the gas inlet passage upon crash and protect the passenger.